This comprises a big category of “supplements”. Over-the-counter (OTC) slimming pills are not the same as prescription weight-loss drugs. Prescription drugs are approved for use (e.g. by the U.S. Food and Drug Administration and other national authorities) only after a stringent approval process that includes pre-clinical trials (experiments on animals), phase-one trials (small-scale human trials), phase-two trials (medium-scale human trials), and phase-three trials (human trials usually involving hundreds or thousands of subjects).
Only after that is the drug released to the public. This is a costly process and the average R&D expenditure for each drug that survives the process and reaches the market is EUR 550 million. Only 1 in 5,000 new substances end up in the market and a period of 12 to 16 years of R&D is needed before the health authorities approve a medicine. This tedious process is designed to ensure public safety, and the measures do not end there – the safety of the drug is monitored even after its launch (post-marketing surveillance) and it may be withdrawn from the market at this stage if the adverse effects are deemed unacceptable.
Why are OTC slimming pills not subjected to the same rigors? It is impossible to police all consumables to such an extent, so for practical reasons, a separate category – food and supplements – has been created, where the controls are much less stringent. These non-prescription medications are not FDA-approved and are not always free of adverse effects, so it is a case of “buyers beware”.
There are a myriad of non-prescription slimming pills, from chitosan to HMB, chromium picolinate, garcinia cambogia, green tea catechins, starch blockers, caffeine and ephedrine. Each purports a different, often novel, mechanism of action. Their advantage is that no doctor’s supervision is required.
Ever wondered why this is? Logically, any drug with a proven harmful side effect requires a doctor’s supervision so that its benefits can be weighed against its risks and the dosage titrated to achieve the optimal risk-benefit ratio. For example, a highly effective antihypertensive would not be made available to the public as a non-prescription drug because the lowering of one’s blood pressure is potentially dangerous.
Imagine a person who, not knowing how to interpret blood-pressure readings, mistakenly thinks he has high blood pressure and gets a sample of this antihypertensive – his blood pressure would drop below normal, causing fainting spells which may lead to accidents.
Now, back to slimming pills. If a slimming pill were highly effective in eliciting weight loss, would it be made available as a non-prescription drug? What if someone with anorexia nervosa (a condition where a person thinks he or she is fat, when it is certainly not the case, and takes drastic measures to lose weight) buys this drug off the shelf? Hence, it is not surprising that OTC medications are not the highly effective ones, because, if they were, their use would need to be supervised by a doctor and they would hence be regulated as prescription drugs.
Diets That Work
Careful examination reveals that popular diet books have a common structure. First, they all have an advocate, usually the author, who relates a compelling personal story of enlightenment about the “true” cause of obesity. The author claims to have found the answer that was missed by others and wants to help others with his newfound knowledge. Second, the book reveals a central “scientific” concept that is distinctly different from mainstream thinking. Finally, the book describes the diet itself, which may promote any combination of macronutrients in various proportions, be it very low-fat (e.g. Ornish and Pritikin), low-carbohydrate (e.g. Atkins), high-protein (e.g. Zone) or a balanced approach.
Are these diets that work? Probably, and the reason is simple. All diet plans impose rules on what you can or cannot eat. By adhering to these plans, the individual consumes less than when eating freely. In short, these diet plans, whatever their philosophy, induce weight loss ultimately through a reduction in caloric intake.